1. Field of the Invention
The present invention relates to an ion shield for fiber optic cables or the like and more particularly to a flexible insulating sheath which may be easily wrapped around one or more cables.
2. Description of the Prior Art
Fiber optic cables are becoming more and more prevalent in data communications and other applications. There are certain environments that subject these cables to ionic radiation. This radiation, for example X-rays, can produce spurious signals in the cable or even degrade the cable. One such environment that may subject these cables to radiation is in nuclear underground testing. There is also a requirement in the military to harden electronics against the effects of nuclear weapons. Fiber optics are included in this catergory. An inexpensive and easy method is needed to shield the fiber optic cables or the like from harmful radiation. Previous attempts to shield fiber optic cables or the like from x-rays have included placing lead bricks or lead sheets around the cables or using a tube of high-Z material that is slipped over the cables to be protected. Each of these methods is very cumbersome. In the case of using lead bricks or sheets a significant amount of extra space is needed for the shield. A tube of high-Z material is more desirable, however, it must be slipped over the cable to be shielded before the cable is placed into the desired circuit. It also has a tendency to collapse when bent (like a sode straw) and damage the cable being shielded.
The previous methods used to shield cables from electromagnetic radiation have been difficult if not impossible in some applications.